1. Field of the Invention
This invention relates to devices for dispensing beverages from large containers, particularly plastic bottles and more particularly devices to prevent loss of carbonation in carbonated beverages after the container has been opened.
2. Background and Prior Art
Large beverage containers of two liters or more recently have become popular. Carbonated beverages in bottles made of polyethylene terephthalate (PET) are widely used for reasons of convenience and cost. The bottles are light in weight and essentially unbreakable but when open over a period of several days, loss of carbonation may become a problem. This is due to equilibration of carbon dioxide between the liquid and the void volume in the bottle, which is essentially by air. This problem is exacerbated if the product warms.
In soda fountains and pubs, systems to introduce carbon dioxide into a beverage are conventional. Such systems are typically not used in homes for reasons of cost and complexity. It remains desirable, however, to prevent loss of carbonation from carbonated drinks to maintain their palatability.
U.S. Pat. No. 262,773 to Hohl discloses a method for lifting a malt beverage from a keg using a gas or liquid forced into a bladder inserted through the bung hole. U.S. Pat. No. 3,244,326 discloses a miniature beer keg having a pressure relief valve at an end opposite to a tap for the admission of make-up air as the contents of the keg are drawn off. U.S. Pat. No. 4,911,334 discloses a device for draining an inverted bottle employing a pair of valves, one of which is a drain valve and the other of which admits air to the top portion of the bottle to prevent gurgling during drainage. U.S. Pat. No. 4,722,463 provides a device similar to U.S. Pat. No. 4,911,334 but for a bottle mounted at an angle, not vertically, and supplements the invention by use of a flexible tube to admit air and the use of a float on the end of said tube to assure it""s presence at the top or head space of a bottle. U.S. Pat. No. 4,809,884 discloses a method for lifting wine by means of an expandible interior bladder and an external pump. U.S. Pat. No. 4,930,666 discloses a valve assembly adapted for use with an inverted juice container mountable in the door of a refrigerator and employing a two part valve incorporating a vent tube to admit air into the container as the juice is withdrawn. U.S. Pat. No. 5,024,353 is directed to a valve and cradle system for dispensing soda from two and three liter plastic bottles while the bottle remains within a refrigerator and employs a two channel valve. The sliding valve includes a vent tube for admitting make-up air into the bottle. U.S. Pat. No. 6,073,811 discloses a cradle and a valve system for lifting carbonated beverages which includes a CO2 cartridge for pressurizing the soda bottle. U.S. Pat. No. 6,220,311 discloses a container for carbonated beverages having an internal bladder which is pressurized to decrease or eliminate void volume by filling with water or air and which employs a second spout at the head of the container.
The prior art fails to disclose a simple device which prevents the admission of air into a partially drained container of carbonated beverage except by requiring a specialized container distinct from bottles in which carbonated beverages are sold in stores.
It is a first object of this invention to provide a method and apparatus for preventing a loss of carbonation in an opened container of carbonated beverage. It is a second objective of this invention to provide a method and apparatus for holding an opened container of carbonated beverage in a refrigerator or on a table. It is a third objective of this invention to provide a means for dispensing carbonated beverage from a refrigerator or table without moving the beverage container.
These and other objectives of this invention may be achieved by providing a base having mounted therein a valve mechanism and which receives the threads of a beverage bottle and by providing, in communication with at least one additional valve, a vent tube passing into at least a portion of the length of the container, the tube being surrounded by a flexible material which serves to separate the carbonated beverage from the make-up air.